A vehicle headlight includes a discharge lamp provided as a light source and a lighting device for lighting the discharge lamp. The discharge lamp and the lighting device are disposed in a lamp chamber that is formed by a front cover and a lamp body.
This lighting device includes a power circuit unit that supplies power to a bulb socket on which a discharge lamp is mounted or a so-called starter used as a starting unit of the discharge lamp. The power circuit unit is connected to the bulb socket or the starter by a harness functioning as a connecting wire.
If multiple harnesses are used as the connecting wire, one end portions of the respective harnesses are connected to power terminals of the power circuit unit by a method, such as welding or soldering, respectively (for example, see Patent Document 1).